"On this earth there are pestilences and there are victims ... one must refuse to be on the side of the pestilence"—Camus

March 01, 2015

The black rat—also known as the ship rat, the roof rat, and the house rat—is actually gray. It has large ears and a tail that’s longer than its body. The black rat (Rattus rattus) probably evolved in tropical Asia, and then was spread around the world by humans—first by the Romans and later by European colonists. According to Juliet Clutton-Brock, the author of “A Natural History of Domesticated Mammals,” it has been blamed for causing “a greater number of deaths in the human species than any natural catastrophe or war.” But perhaps the rat has gotten a bad rap?

A paper published the other day in the Proceedings of the National Academy of Sciences, which quickly made headlines all around the world, argues that the prevailing theory of how the Black Death spread is unfair to rats. Really, the authors of the study contend, the animal responsible was a Central Asian species like the great gerbil. (Great gerbils are only distantly related to the fuzzy rodents that American kids keep as pets, though they may look a lot alike to parents.)

The authors of the study were trying to address one of the mysteries about the Black Death. Why, after killing something like twenty-five million people in Europe in the mid-fourteenth century, did outbreaks of plague keep flaring up and then dying down again? (The Great Plague of London, in the mid-seventeenth century, killed roughly a fifth of the city’s population.)

The prevailing theory is—or was—that bacteria responsible for the plague, Yersinia pestis, lived on Europe’s black-rat population. The rats transmitted the bacteria to fleas, which, episodically, transmitted them to humans. But the scientists who conducted the PNAS study concluded that there were no “permanent plague reservoirs in medieval Europe.”

Instead, they posit, the plague bacterium kept being reintroduced to Europe from Asia, where it lived on the native rodent populations. They came to this conclusion after comparing tree-ring records from Europe and Asia with records of plague outbreaks.

What they found was that plague seemed to show up at port cities in Europe several years after climate conditions favored a burst of population growth among rodents in Central Asia. (This theory does not completely exonerate black rats, as they would still have helped their Asian rodent brethren spread the disease once it reached Europe.)

“We show that, wherever there were good conditions for gerbils and fleas in Central Asia, some years later the bacteria shows up in harbor cities in Europe and then spreads across the continent,” one of the authors of the study, Nils Christian Stenseth, a biologist at the University of Oslo, told the BBC.

Plague is no longer a worry in Europe, although there are still occasional outbreaks in other parts of the globe. What’s perhaps the most important insight from the study has little to do with Yersinia pestis or giant gerbils. It’s that climate and human health are, in significant though often roundabout ways, related. As the climate changes, this has important—and, at the same time, hard to predict—implications.

The list of diseases (and disease vectors) that could potentially be affected by climate change is a long and various one. It includes tick-borne diseases, such as Lyme disease, and mosquito-borne diseases—dengue fever, West Nile virus, malaria. It also includes waterborne diseases, such as cholera, and fungal diseases, such as valley fever. An upcoming issue of Philosophical Transactions B, a journal of Britain’s Royal Society, is wholly devoted to the subject of “climate change and vector-borne disease."

December 31, 2014

There is not going to be a new plague in Britain. It is necessary to be vigilant about health workers returning from Ebola hotspots such as Sierra Leone, and it is only a proper recognition of the risks they have run that they are properly checked in decent conditions when they return. But it is not going to happen here.

The last recognised outbreak of plague in Britain ended with the great fire of London in 1666, although that is probably less than the whole truth. There may have been small outbreaks right into the 20th century. Both scientists and historians are still trying to explain why 1666 was its last serious appearance.

There won’t be one answer. But some possibilities are clear. For example, without necessarily understanding why, the Black Death’s contagious nature was so well understood that it was considered perfectly acceptable to wall up an entire household if one member showed symptoms. Whole villages were left to die. Plague bowls, where charitable neighbours might leave alms, can still be found on parish boundaries.

Other explanations range from viral mutation and possible misdiagnosis to statistical over-inflation. Yet among the many unknowns, the dark holes of our knowledge, is what happened to wealth and wages in the aftermath of a major outbreak.

In 2008, a group of academics reassessed GDP in England from 1300–1700, challenging the idea that it had hardly changed over 400 years. They found that rather than stagnation in individual earnings, there was steady growth from the second half of the 17th century, particularly after the Black Death. One obvious explanation is that a sharp fall in population forced up wages, and higher wages encouraged what the academics called an “industrious revolution”.

One piece of evidence historians now think they can be firm about is a differential rate of death. Many more poor people died than rich people. According to figures gleaned from clergy, senior clerics, bishops and such like, died at the rate of about one in four while for those working among the rural poor, the rate was nearer one in two. That is, poverty kills.

Listening to the NHS staff returning from fighting Ebola in Sierra Leone, it is obvious that poverty still kills as efficiently as it always has. One doctor on BBC Radio 4’s Today programme this morning explained that their clinic had no access to any special treatment, but that simply by rehydrating patients they were immediately seeing better than 50% recovery rates.

He added that there was not yet any scientific evidence that the new vaccines or treatments made a difference. It may be that outcomes that are just as good and much, much cheaper will come from the absolute fundamentals of good basic care and hygiene.

December 09, 2014

The ECDC Communicable Disease Threats Report is a weekly bulletin intended for epidemiologists and health professionals in the area of communicable disease prevention and control. This issue covers the period 30 November–6 December 2014 and includes updates on:

Ebola virus disease – West Africa

An outbreak of Ebola virus disease (EVD) has been ongoing in West Africa since December 2013, mainly affecting Guinea, Liberia and Sierra Leone. Up to 2 December, WHO has reported 17 256 confirmed, probable, and suspected cases of Ebola virus disease, including 6 113 deaths, in five affected countries (Guinea, Liberia, Mali, Sierra Leone and the United States of America) and three previously affected countries (Nigeria, Senegal and Spain). Since 25 November no additional cases of EVD have been reported in Mali.

On 2 December WHO declared Spain Ebola-free as 42 days have passed since the confirmed case tested negative.

ECDC published an update to its rapid risk assessment on 18 November 2014

Outbreak of measles linked to an international dog exhibition - Slovenia

An outbreak of measles was reported in Slovenia on 27 November 2014. The outbreak was likely to have been caused by common exposure at an international dog exhibition in the country. Fifteen cases of measles reported in November (11 confirmed and 4 probable), have a history of visiting the exhibition that took place in Vrtojba close to Nova Gorica on 8–9 November 2014.

Plague outbreak - Madagascar

An outbreak of plague has been evolving in Madagascar since 31 August 2014 when the first case was notified in a male child who died on 3 September. As of 5 December 2014, 138 cases and 47 deaths (CFR 34%) have been reported.

November 24, 2014

Endemic in rural Madagascar, the plague has recently appeared in the capital Antananarivo, where the proliferation of rats and fleas carrying the disease concerned.

A young woman died of the disease on November 11 in a slum in the capital, unsafe area where homes are stacked between swamps and rice fields.

Another non-fatal cases were reported in this city of two million inhabitants.

"There is now a risk of rapid development of the disease due to the high population density in the city and the weaknesses of the health system," warns the World Health Organization (WHO) has reported 119 plague cases in the country this year, including 40 deaths.

In the district of Ankasina where lived the young woman of 21, we remain incredulous.

"We lived here since 1975, with the same living conditions, so why it is now that we have the plague?" Asks Bernadette Rasoarimanana, the mother of the victim.

"One has to admit, our neighborhood is really dirty and neglected by the state, invaded by rats, and this long," sighs Rakotojaona Adolphe, a neighbor.

The last case of plague in the capital dates back to ten years, according to Christophe Rogier, the Director General of the Institut Pasteur of Madagascar.

"It is possible that the plague has continued to circulate in Antananarivo for ten years without it human touch," he argues. In contrast, rats that swarm in the slums of the city could continue to be affected by the virus. "Rats are natural reservoirs of plague, there are rats that survive the plague too!"

Another problem, according to WHO: resistance bulleted deltamethrin, an insecticide used to control them.

November 21, 2014

As reported in these columns this week , be careful because this is the season of plague . Unfortunately, awareness of hygiene and public health are not always effective. The first victim of the plague died this week.

This is a young woman of 21, living in the popular Ankasina 67-ha area. There was a malfunction in the treatment of this case, because the first doctors who diagnosed did not report the probable case of plague, they even let the family take the body of the young woman who has been ensured for 3 days according to the Malagasy tradition.

It was only after doctors BMH (municipal health office) came to the sampling and analysis at the Institut Pasteur, results were positive. But the family of the victim refused to give the body the doctors BMH and gendarmes came to the rescue.

"We will bury our loved tradition of ourselves as the first doctor who saw him die gave the records necessary to do so," insists the family.

The authorities do not know what to do, they just sprayed disinfectant around the house of the victim. They will surely be forced to return to convince all those who were in contact with the victim at death to be diagnosed and treated. Wide program to the extent that it is certainly no less than a hundred people to convince, just for funeral wakes.

And that the Prime Minister, Minister of Health, says it can cope with the disease Ebola if ever happens in Madagascar when we can not even coordinate this kind of problem. Pray, as most people say, for Ebola does not happen here because we can not really rely on the leaders.

On 4 November 2014, WHO was notified by the Ministry of Health of Madagascar of an outbreak of plague. The first case, a male from Soamahatamana village in the district of Tsiroanomandidy, was identified on 31 August. The patient died on 3 September.

As of 16 November, a total of 119 cases of plague have been confirmed, including 40 deaths. Only 2% of reported cases are of the pneumonic form.

Cases have been reported in 16 districts of seven regions. Antananarivo, the capital and largest city in Madagascar, has also been affected with 2 recorded cases of plague, including 1 death. There is now a risk of a rapid spread of the disease due to the city’s high population density and the weakness of the healthcare system.

The situation is further complicated by the high level of resistance to deltamethrin (an insecticide used to control fleas) that has been observed in the country.

Public health response

The national task force has been activated to manage the outbreak. With support from partners – including WHO, the Pasteur Institute of Madagascar, the “Commune urbaine d’Antananarivo” and the Red Cross – the government of Madagascar has put in place effective strategies to control the outbreak. Thanks to financial assistance from the African Development Bank, a 200,000 US dollars response project has been developed.

WHO is providing technical expertise and human resources support. Measures for the control and prevention of plague are being thoroughly implemented in the affected districts. Personal protective equipment, insecticides, spray materials and antibiotics have been made available in those areas.

​This issue covers the period from 20 to 26 July 2014 and includes updates on:

Mass gathering monitoring: Commonwealth Games 2014

In collaboration with Health Protection Scotland, ECDC enhanced its monitoring activities during the Commonwealth Games in Scotland (23 July to 3 August 2014). During the past week, ECDC has not detected any events of public health significance to the Games.

West Nile virus

During the past week, no new human cases have been reported in the EU or in neighbouring countries. West Nile fever in humans is a notifiable disease in the EU.

Chikungunya, the Caribbean

Most of the areas previously affected by the outbreak that has been on-going since December 2013 continue to report cases. The situation is particularly severe on the island of Hispaniola, i.e. Haiti and the Dominican Republic, and Guadeloupe. Costa Rica, Venezuela, the Cayman Islands and the Republic of Trinidad and Tobago have now also notified local transmission of chikungunya infection. Jamaica and Colombia have reported imported cases during week 29.

ECDC published a risk assessment on 25 June and an epidemiological update on 30 June.

Outbreak of Ebola Virus Disease (EVD), West Africa

During the last week, the affected countries have reported 111 new cases and 47 new fatalities. The largest increase in cases since the previous update was reported in Sierra Leone, followed by Liberia and Guinea. As a follow-up action to the Emergency Ministerial meeting held in Ghana, the World Health Organization established a sub-regional outbreak coordination centre in Conakry (Guinea) on 16 July 2014 to meet the needs to control the outbreak.

This outbreak has been affecting Guinea, Liberia and Sierra Leone since December 2013. While this is the largest EVD outbreak reported, the risk of infection for travellers is considered very low.

ECDC published a risk assessment on 9 June and an epidemiological update on 17 July.

Middle East Respiratory Syndrome Coronavirus (MERS-CoV)

Since the last CDTR, one new fatal case has been reported by Iran. Saudi Arabia has reported additional deaths in previously reported cases. ECDC published its updated rapid risk assessment on MERS-CoV on 31 May 2014 and an epidemiological update on 5 June 2014.

Pneumonic plague, China

On 17 July 2014, Chinese health authorities reported a fatal case of pneumonic plague in a 38-year-old man from Yumen City (Gansu province). The patient was admitted to hospital on 15 July 2014 and died one day later. He was a farm worker and had a history of exposure to a dead marmot that he had fed his dog. In response, the Chinese authorities issued an emergency alert for the region and implemented control measures including isolation and prophylactic treatment of the patient’s close contacts. No further cases have been reported as of 23 July 2014, and the quarantine has been lifted as of 24 July.

A Chinese town has been sealed off and 151 people placed in quarantine since last week after a man died of bubonic plague, state media said Tuesday (July 22).

The 30,000 people living in Yumen in the northwestern province of Gansu are not being allowed to leave, and police at roadblocks on its perimeter are telling motorists to find alternative routes, state broadcaster China Central Television (CCTV) said.

Other reports said that earlier this month the 38-year-old victim had found a dead marmot, a small furry animal which lives on grasslands and is related to the squirrel.

He chopped it up to feed his dog but developed a fever the same day. He was taken to hospital after his condition worsened and died last Wednesday.

"The city has enough rice, flour and oil to supply all its residents for up to one month," CCTV added.

"Local residents and those in quarantine are all in stable condition."

CCTV said authorities are not allowing anyone to leave, although a previous report by the China Daily newspaper said "four quarantine sectors" had been set up in the city.

A Chinese city has been sealed off and 151 people have been placed in quarantine since last week after a man died of bubonic plague, state media said.

The 30,000 residents of Yumen, in the north-western province of Gansu, are not being allowed to leave, and police at roadblocks on the perimeter of the city are telling motorists to find alternative routes, China Central Television (CCTV) said.

A 38-year-old man died last Wednesday, the report said, after he had been in contact with a dead marmot, a small furry animal related to the squirrel. No further plague cases have been reported.

CCTV said officials were not allowing anyone to leave. The China Daily newspaper said four quarantine sectors had been set up in the city.

"The city has enough rice, flour and oil to supply all its residents for up to one month," CCTV added. "Local residents and those in quarantine are all in stable condition." No further cases have been reported.

Bubonic plague is a bacterial infection best known for the Black Death, a virulent epidemic that killed tens of millions of people in 14th-century Europe. Primarily an animal illness, it is extremely rare in humans.

July 20, 2014

The recently documented mistakes at federal laboratories involving anthrax, flu and smallpox have incited public outrage at the government’s handling of dangerous pathogens. But the episodes were just a tiny fraction of the hundreds that have occurred in recent years across a sprawling web of academic, commercial and government labs that operate without clear national standards or oversight, federal reports show.

Spurred by the anthrax attacks in the United States in 2001, an increase in “high-level containment” labs set up to work with risky microbes has raised the number to about 1,500 from a little more than 400 in 2004, according to the Government Accountability Office.

Yet there has never been a national plan for how many of them are needed, or how they should be built and operated. The more of these labs there are, the G.A.O. warned Congress last week, the greater the chances of dangerous blunders or sabotage, especially in a field where oversight is “fragmented and largely self-policing.”

As the labs have multiplied, so have mishaps. According to a 2012 article by researchers from the Centers for Disease Control and Prevention, the number of reported accidents involving microbes that can cause severe illnesses grew rapidly — from just 16 in 2004 to 128 in 2008 and 269 in 2010, the last year reported. Many of the accidents involved leaks, spills or other releases of infectious material inside the laboratories, potentially infecting workers and often requiring extensive decontamination.

Another report, by the Department of Homeland Security in 2008, provided a rare glimpse into the types of accidents that have occurred at high-level labs around the country, often at universities.

Lab workers at different sites accidentally jabbed themselves with needles contaminated by anthrax or West Nile virus. An air-cleaning system meant to filter dangerous microbes out of a lab failed, but no one knew because the alarms had been turned off. A batch of West Nile virus, improperly packed in dry ice, burst open at a Federal Express shipping center. Mice infected with bubonic plague or Q fever went missing. And workers exposed to Q fever, brucellosis or tuberculosis did not realize it until they either became ill or blood tests detected the exposure.

The good news is that relatively few lab workers have become ill from accidental exposures: only 11 from 2004 to 2010, according to the C.D.C. report. None died, and none infected other people.

Richard H. Ebright, a molecular biologist and laboratory director from Rutgers University, said he had “no confidence” in the safety of the many labs that have sprung up since 2001. He suggested there was a culture of complacency at some of them, as well as hubris among some researchers who believe they do not need oversight or management.